5 Minutes for Reflection. A Collection of the Best Soviet Puzzles

At what speed must a car move for a red traffic light to appear green to the driver? Which is heavier - a ton of wood or iron? Why does a stream babble? If you and your child enjoy engaging puzzles and tasks, then this book is for you. It contains dozens of unusual problems related to physics, geography, astronomy, and other sciences, as well as chess studies, mathematical and optical tricks, and crosswords of varying difficulty levels. By pondering them, you will train your logic and learn many curious scientific facts. And if any task proves too difficult, at the end of each section you will find answers with detailed comments on how to reason correctly. With the help of illustrations, the tasks become even more interesting, and many of them - for example, crosswords or chess - can be solved directly in the book.